Hormonal contraception works primarily by preventing ovulation, but it may also thicken the cervical mucus inhibiting sperm penetration.[2][3][4] Hormonal contraceptives also have effects on the endometrium,[5][6] that theoretically could affect implantation,[7][8][9][10]

CIC is administered by intramuscular injection into the deltoid, gluteus maximus, or anterior thigh.[1] It is ideally administered every 28 to 30 days, though it has been demonstrated to be effective up to 33 days.[1]